Get a garden hose thread pressure gauge. Turn off the WHs, or move to vacation. Monitor the water pressure.
You can get one with a tattletale/lazy hand to record the peak. Now that hand going up is not for sure that your water pressure went that high. Vibration can make that hand move.
If you want, you can take a movie of the pressure gauge with your cellphone.
Gauge can go on hose spigot, laundry tap, or the drain on a water heater.
It seems unfair to try to get plumbers to come out for free to tell you that you don't need a PRV, but only a thermal expansion tank.
You can get one with a tattletale/lazy hand to record the peak. Now that hand going up is not for sure that your water pressure went that high. Vibration can make that hand move.

Watts 3/4 in. Plastic Water Pressure Test Gauge DP IWTG - The Home Depot
Test water supply pressures within a distribution system using this Watts Plastic Water Pressure Test Gauge. Features a copper alloy tube sensing element.
www.homedepot.com
Gauge can go on hose spigot, laundry tap, or the drain on a water heater.
It seems unfair to try to get plumbers to come out for free to tell you that you don't need a PRV, but only a thermal expansion tank.